It is common for vehicles to include components or parts that are secured to one another while being moveable relative to one another. For instance, in Class 8 heavy duty vehicles, the cab is typically moveably mounted to the chassis to accommodate and isolate vibrations, rocking, tilt, etc., therebetween. Furthermore, the chassis or frame may also include components that are movably secured to one another to accommodate movements in the frame over various road conditions.
Movable components of a vehicle are generally secured to one another in one of a variety of ways. For instance, the components may be secured to one another through a linear bearing or bushing mounting assembly that enables movement in a travel direction with low resistance, but substantially prevents any movement in a perpendicular cross-travel direction.
The use of linear bearings and/or bushings has significant drawbacks, especially when used on the exterior of a vehicle. For instance, linear bearings and bushings have the propensity to bind or wear out in the presence of environmental contamination, such as debris, water, ice, etc. The possibility of contamination usually necessitates some method of sealing the linear bushing or bearing to limit exposure to the environmental contaminants, which drives up the cost of the linear bearing or bushing mounting assembly. The seals also tend to degrade over time, requiring replacement of the seals and/or exposing the linear bearing or bushing assembly to environmental contaminants. Linear bearings also tend to be inherently expensive due to a large number of precision parts. Bushings are a less expensive option; however, bushings are a lower performance, less durable solution to linear bearings. More particularly, the durability of the bushing generally decreases as the parts continue to slide and wear on one another. The performance is even further compromised by environmental contaminants.
Another common solution that is not similarly affected by environmental conditions is the utilization of a soft, elastic material such as natural rubber to mount the vehicle components together. Because the elastic material is soft, it allows some movement between the parts. Moreover, the dimensions of the elastic material can be configured to make the elastic material stiffer in a first direction, while allowing movement in, for instance, a second, perpendicular direction. More specifically, a rubber block that is essentially rectangular is longer in one direction; and therefore, it is more difficult to move the components along the length of the block versus the thinner, perpendicular direction. However, movement in the perpendicular direction (across the thinner portion of the rubber block) typically requires large strains in the rubber with only limited displacement capability.
Thus, it can be appreciated that an improved mounting assembly for movably mounting components to one another, without being susceptible to environmental contamination and without requiring large strains in the material, is desired.